Electroosmotic pump

ABSTRACT

The present invention discloses a path-type liquid medicine delivery electro-osmosis pump that can be applied to a wearable medicine device. 
     An electro osmosis pump according to the present invention includes: a connector provided with a liquid medicine inlet and a liquid medicine outlet; a check valve assembly combined to one side of the connector; and a driver that is connected to the other side of the connector and moves the liquid medicine toward the liquid medicine outlet by applying pressure to the liquid medicine while being separated from the liquid medicine, which passes through the check valve assembly.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.16/326768, filed on Feb. 20, 2019, as the U.S. National Phase under 35U.S.C. § 371 of International Application PCT/KR2017/008292, filed Aug.1, 2017, which claims priority to Korean Patent Application No.10-2016-0112131, filed Aug. 31, 2016. Each of these applications ishereby incorporated by reference in its entirety.

TECHNICAL FIELD

The present invention relates to a patch-type liquid medicine deliverydevice attached to a human body or an electro-osmosis pump fortransmission of liquid medicine, which may be applied to a wearablemedical device.

BACKGROUND ART

An electro-osmosis pump is a pump that uses a phenomenon of fluidmovement which occurs when a voltage is applied to opposite ends of acapillary or a porous separation membrane. The electro-osmosis pump canbe manufactured to be very small in size compared to a generalmechanical pump, and generates no noise and consumes less power.

For example, international patent publication No. WO 2011/112723discloses an electro osmosis pump that includes a ceramic membranedisposed between a porous sliver/oxidized silver anode and a poroussliver/oxidized cathode.

The above-stated patent discloses a liquid medicine delivery device inwhich electrodes are formed at opposite ends of the ceramic separationmembrane, and when a predetermined potential is applied to theelectrodes, a pressure that corresponds to the corresponding potentialis generated and the device uses the pressure. The liquid medicinedelivery device additionally uses two electric fluid chambers and aneedle for injection of liquid medicine.

However, the electro osmosis pump used in the liquid medicine deliverydevice has a structure in which liquid medicine to be delivered andwater, which is an operation fluid used for driving of the pump areseparated from each other by oil, and thus unexpected mixing of theliquid medicine and water may occur at any time in an interface betweenthe liquid medicine and water.

In the electro osmosis pump, liquid medicine, which is an object to bedelivered, and water, which is an operation fluid, need to be separatedfrom each other. Liquid medicine is a mixture of various substances, anda biologically active substance in components of the mixture may beoxidized or reduced in a potential for driving of the electro osmosispump. In addition, when the liquid medicine directly contacts theelectrode, a high molecular substance such as protein is adsorbed to theelectrodes, thereby deteriorating performance of the pump, andaccordingly, it is preferable that the electrodes and the liquidmedicine need to be separated from each other. However, a conventionalmethod cannot sufficiently satisfy such a condition.

In addition, an amount of power to be consumed for driving of the pumpis a factor that determines practical utility when the pump is appliedto a patch-type liquid medicine delivery device or a wearable medicaldevice attached to a human body, and accordingly, a small-sized pump,which can be driven with low power, is required.

DISCLOSURE Technical Problem

The present invention has been made in an effort to resolve theabove-described problems, and provides an electro osmosis pump that canbe stably driven by preventing liquid medicine, which is an object to bedelivered, and operation fluid from being mixed with each other, therebyimproving merchantability, and can prevent a side effect thereby thetherapeutic effect for a patient.

In addition, another purpose of the present invention is to provide anelectro osmosis pump that can maximize fluid transfer efficiency withrespect to power consumption.

Technical Solution

In order to achieve such a purpose, the present invention provides anelectro osmosis pump that includes: a connector provided with a liquidmedicine inlet and a liquid medicine outlet; a check valve assemblycombined to one side of the connector; and a driver that is connected tothe other side of the connector and moves the liquid medicine toward theliquid medicine outlet by applying pressure to the liquid medicine whilebeing separated from the liquid medicine, which passes through the checkvalve assembly.

The check valve assembly may include: an inflow check valve that isdisposed in the liquid medicine inlet to move the liquid medicine in onedirection; and an discharge check valve that is disposed in the liquidmedicine outlet to discharge the liquid medicine delivered through theinflow check valve.

It is preferable that the check valve assembly is combined to theconnector and includes a liquid medicine inflow extension pipeline and aliquid medicine discharge extension pipeline, the liquid medicine inflowextension pipeline is connected to the liquid medicine inlet and theliquid medicine discharge extension pipeline is connected to the liquidmedicine outlet, and an inflow check valve is disposed in the liquidmedicine discharge extension pipeline and a discharge check valve isdisposed in the liquid medicine discharge extension pipeline.

It is preferable that a first fixing hole that fixes the inflow checkvalve is formed in the liquid medicine inflow extension pipeline, and asecond fixing hole that fixes the discharge check valve is formed in theliquid medicine discharge extension pipeline.

It is preferable that the driver includes: a first diaphragm that iscombined to the connector and blocks liquid medicine of the check valveassembly; a first pump housing that is combined to the first diaphragmand provided with a space where an operation fluid is received; a firstpower supply line that is combined to the first pump housing andreceives power; a first electrode connected to the first power supplyline; a membrane of which one side is combined to the first electrode; asecond electrode combined to the other side of the membrane; a secondpower supply line that supplies power to the second electrode; a secondpump housing combined to one side of the second electrode and providedwith a space where an operation fluid is received; and a seconddiaphragm combined to the second pump housing.

It is preferable that the first pump housing is provided with a spacethat penetrates along an axial direction and the space of the first pumphousing is blocked by the first diaphragm and the first electrode, andthe second pump housing is provided with another space that penetratesalong the axial direction and the space of the second pump housing isblocked by the second electrode and the second diaphragm.

It is preferable that a space in which liquid medicine is introducedinto through the liquid medicine inlet and discharged through the liquidmedicine inlet is formed between the connector and the first diaphragm.

It is preferable that the membrane is formed of a porous materialthrough which an operation fluid and ions can be transferred.

The membrane is preferably formed of an insulator.

It is preferable that the first diaphragm or the second diaphragm isprovided with a wrinkle portion that is formed as protrusions anddepressions.

Advantageous Effects

According to the present invention, a pump operation fluid and a fluidto be delivered such as liquid medicine are separated from each other bya flexible diaphragm and thus an active component included in the fluidto be delivered can be prevented from being spoiled due to anelectro-chemical reaction by a voltage applied to an electrode.

In addition, according to the present invention, a component included inthe pump operation fluid can be prevented from being fixed with theliquid medicine, and thus various transfer fluids can be applied indesign of a patch-type liquid medicine delivery device, therebyincreasing the degree of freedom in a design. That is, the presentinvention enables the design of a patch-type liquid medicine deliverydevice that can selectively supply an optimum liquid medicine to apatient suffering from a specific disease such as diabetes, or can beapplied to patients suffering from various diseases.

Further, the present invention provides an effect of improvingmerchantability of the electro osmosis pump driven with low power andhigh efficiency by applying a check value having a very low openingpressure and increasing a reaction speed of the check value.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an external appearance of an electroosmosis pump provided for description of an exemplary embodiment of thepresent invention.

FIG. 2 is a perspective view of the electro osmosis pump of FIG. 1,viewed from a different angle.

FIG. 3 is an exploded perspective view of FIG. 1.

FIG. 4 is a cross-sectional view of FIG. 1, taken along the line IV-IV.

FIG. 5 is a cross-sectional view of FIG. 1, taken along the line V-V.

MODE FOR INVENTION

The present invention will be described more fully hereinafter withreference to the accompanying drawings, in which exemplary embodimentsof the invention are shown. As those skilled in the art would realize,the described embodiments may be modified in various different ways, allwithout departing from the spirit or scope of the present invention. Thedrawings and description are to be regarded as illustrative in natureand not restrictive. Like reference numerals designate like elementsthroughout the specification.

FIG. 1 and FIG. 2 are perspective view provided for description of anexemplary embodiment of the present invention, FIG. 3 is an explodedperspective view of FIG. 1, FIG. 4 is a cross-sectional view of FIG. 1,taken along the line IV-IV, and FIG. 5 is a cross-sectional view of FIG.1, taken along the line V-V, which illustrates an electro-osmosis pump.

An electro-osmosis pump according to an exemplary embodiment of thepresent invention includes a connector 1, a check valve assembly 3, anda driver 5.

The check valve assembly 3 may be combined to one side of the connector1 and the driver may be combined to the other side of the connector 1.The connector 1 is provided with a barrier rib 1 a that partitions thecheck valve assembly 3 and the driver 5. The barrier rib 1 a includes aliquid medicine inlet 1 b and a liquid medicine outlet 1 c.

The liquid medicine inlet 1 b and the liquid medicine outlet 1 c aredisposed at a distance from each other, and penetrate the barrier rib 1a.

Liquid medicine to be injected into a human body is put into the liquidmedicine inlet 1 b, and the liquid medicine outlet 1 c may be a paththrough which the liquid medicine put into the liquid medicine inlet 1 bis discharged so as to be injected back into the human body.

The check valve assembly 3 may include a valve housing 7, an inflowcheck valve 9, a discharge check valve 11, a first fixing hole 13, and asecond fixing hole 15.

The valve housing 7 includes a liquid medicine inflow extension pipeline7 a and a liquid medicine discharge extension pipeline 7 b. The valvehousing 7 may be combined to one side of the connector 1. In addition,the liquid medicine inflow extension pipeline 7 a is connected to theliquid medicine inlet 1 b, and the liquid medicine discharge extensionpipeline 7 b is connected to the liquid medicine outlet 1 c.

The inflow check valve 9 is disposed in the liquid medicine inflowextension pipeline 7 a. The inflow check valve 9 may let liquid medicineinjected into a human body pass to the liquid medicine inlet 1 b andblock movement of the liquid medicine in the reverse direction.

The discharge check valve 11 is disposed in the liquid medicinedischarge extension pipeline 7 b. The discharge check valve 11 may letthe liquid medicine passed through the liquid medicine inlet 1 b pass ina direction of injection into the human body, and blocks movement in thereverse direction.

As the inflow check valve 9 and the discharge check valve 11, duckbillvalves that are flexible and have a low open-pressure may be used. Fluidtransmission efficiency compared to a power consumption amount isincreased by the inflow check valve 9 and the discharge check valve 11,thereby enabling long-time operation and improving productivity.

The first fixing hole 13 is fitted into the liquid medicine inflowextension pipeline 7 a to fix the inflow check valve 9. The secondfixing hole 15 is fitted into the liquid medicine discharge extensionpipeline 7 b to fix the discharge check valve 11.

In addition, the first fixing hole 13 and the second fixing hole 15preferably have pipelines through which liquid medicine can pass.

In the exemplary embodiment of the present invention, the inflow checkvalve 9 and the discharge check valve 11 are combined to the valvehousing 7, but this is not restrictive, and the inflow check valve 9 andthe discharge check valve 11 may be respectively combined to the liquidmedicine inlet 1 b and the liquid medicine outlet 1 c provided in theconnector 1. In this case, the valve housing 7 is integrally formed withthe connector 1 so that it can be manufactured with a simpler structure.According to the other exemplary embodiment of the present invention,the number of parts is reduced so that manufacturing cost can be moresaved, and the product can be manufactured to be more compact.

The driver 5 is combined to one side of the connector 1. The driver 5 ispreferably disposed opposite to a side where the check valve assembly 3is combined. The driver 5 is preferably disposed apart from the liquidmedicine that passes through the check valve assembly 3. The driver 5applies pressure to the liquid medicine passed through the check valveassembly 3 such that the liquid medicine can pass through the liquidmedicine outlet 1 c.

The driver 5 may include a first diaphragm 17, a first pump housing 19,a first power supply line 21, a first electrode 23, a membrane 25, asecond electrode 27, a second power supply line 29, a second pumphousing 31, and a second diaphragm 33.

The first diaphragm 17 is combined to one side of the connector 1. Aspace is provided between the first diaphragm 17 and the connector 1.That is, the first diaphragm 17 is combined to the connector 1, whilemaintaining a certain space in the connector 1. Thus, liquid medicine atthe check valve assembly 3 maintains a state of being isolated ratherthan moving toward the driver 5 by the first diaphragm 17.

The first diaphragm 17 of which a plane that forms the first diaphragm17 can iteratively move in a predetermined section in an axial directionby a pressure generated from the driver 5. A wrinkle portion may beprovided in the first diaphragm 17 to allow the plane to smoothly movealong the axial direction (i.e., the x-axis direction in FIG. 1).

The first diaphragm 17 is combined to one side of the first pump housing19. The first pump housing 19 is provided with a space 19 a thatpenetrates along an axial direction. Thus, one side of the space 19 a ofthe first pump housing 19 may be closed by the first diaphragm 17.

The first electrode 23 is combined to the other side of the first pumphousing 19 so that the space 19 a formed by the first pump housing 19may be closed. In addition, the first pump housing 19 may accommodateoperation fluid such as water and the like in the space 19 a providedtherein.

The first pump housing 19 may be provided with a fluid injection holeportion 19 b at an external circumference thereof. Such a hole portion19 b may be sealed after the operation fluid is injected into the firstpump housing 19. Thus, the operation fluid of the driver 5 may beseparated from the liquid medicine at the check valve assembly 3.

The first power supply line 21 may supply power to the first electrode23. The first power supply line 21 is disposed along an edge of thefirst pump housing 19, and may be fixed to the first electrode 23 bycontacting the same. The first power supply line 21 is preferablydisposed between the first pump housing 19 and the first electrode 23.However, according to another exemplary embodiment of the presentinvention, the first power supply line 21 may supply power to the firstelectrode 23, and may be disposed between the first electrode 23 and themembrane 25.

The first electrode 23 is formed in the shape of a plate and thus mayclose the space 19 a of the first pump housing 19. That is, the firstpump housing 19 may form the space 19 a with the first diaphragm 17 andthe first electrode 23. In addition, the operation fluid such as waterand the like is accommodated in the space 69 a of the first pump housing19.

The membrane 25 may be formed of a porous material through which theoperation fluid and ions can be tranferred. The membrane 25 ispreferably made of an insulator such as a ceramic and the like. When themembrane 25 is formed of an insulator, an electro-chemical reactionmaterial used in the first electrode 23 and the second electrode 27 isconsumed or desorbed due to long-term driving of the electro-osmosispump and thus the porous membrane 25 is exposed. However, in this case,even when conventional carbon paper or carbon cloth is used, a sidereaction such as electrolysis of water, which occurs due to exposure tocarbon paper or carbon cloth, does not occur. Thus, unnecessary powerconsumption due to a side reaction can be prevented. Therefore,according to the present invention, a safe driving characteristic can beprovided and durability can be improved.

The membrane 25 may be used by processing a flexible non-conductivematerial such as a polymer resin, rubber, urethane, or a plastic filminto a thin film form.

The second electrode 77 is disposed at the other side of the membrane75. That is, the membrane 25 is preferably disposed between the firstelectrode 23 and the second electrode 27. The second power supply line29 may supply external power to the second electrode 27. The secondpower supply line 29 may be combined to an edge of the second pumphousing 31. However, the second power supply line 29 may have anyalignment structure as long as it has a structure for supplying power tothe second electrode 27.

The shape of the second pump housing 31 is the same as or similar to theshape of the first pump housing 19. Another space 31 a that penetratesthe second pump housing 31 along an axial direction is provided in thesecond pump housing 31. As in the first pump housing 19, a hole portion31 b that penetrates the space 31 a may be provided in the second pumphousing 31. The hole portion 31 b of the second pump housing 31 may besealed by a sealant or filled by welding and the like after operationfluid is injected therein.

The second diaphragm 33 is combined to one side of the second pumphousing 31 and thus may close the space 31 a provided in the second pumphousing 31.

That is, the second pump housing 31 may close the space 31 a by usingthe second electrode 27, which is formed in the shape of a plate, andthe second diaphragm 33.

A wrinkle portion 33 a may be formed in a plane of the second diaphragm33. The wrinkle portion 33 a formed in the second diaphragm 33 may beformed of protrusions and depressions that protrude in the axialdirection with reference to a cross-section. The wrinkle portion 33 a ofthe second diaphragm 33 enhances performance of pumping by sufficientlymoving the plane of the second diaphragm 33 along the axial direction.

In the exemplary embodiment of the present invention, the wrinkleportion 33 a is formed in the second diaphragm 33, but depending onexemplary embodiments, a wrinkle portion may be also formed in the firstdiaphragm 17. In addition, a wrinkle portion that can be formed in thefirst diaphragm 17 or the second diaphragm 33 maximizes deformation ofthe first diaphragm 17 and the second diaphragm 33 with small energy,thereby reducing energy consumption. That is, the driver 5 can be drivenfor a long period of time with a small external power source.

As shown in FIG. 4 and FIG. 5, the above-described first pump housing19, the first power supply line 21, the first electrode 23, the membrane25, the second electrode 27, the second power supply line 29, and thesecond pump housing 31 may be air-tightly sealed from the outside by anencapsulant S. That is, the first power supply line 21, the firstelectrode 23, the membrane 25, the second electrode 27, and the secondpower supply line 29 are formed relatively smaller than the first pumphousing 19 and the second pump housing 31 in size, and thus theencapsulant S may be disposed in a circumferential portion (i.e., aportion exposed to the outside and a portion that forms a groove or aspace with reference to a cross-section) between the first pump housing19 and the second pump housing 31 while the first power supply line 21,the first electrode 23, the membrane 25, the second electrode 27, andthe second power supply line 29 are in an assembled state. Such anencapsulant S may form an encapsulation layer that maintains air-tightencapsulation from the outside.

As the encapsulant, an adhesive such as a hot melt adhesive, an epoxyadhesive, a polyurethane adhesive, or a cyanoacrylate adhesive may beused. However, the encapsulant is not limited to such examples, and anymaterial that is rigidly cured to prevent leakage of operation fluid andprevent deformation of an external appearance of a configuration elementis applicable.

An operation process of the above-described exemplary embodiment of thepresent invention will now be described in detail.

First, power is supplied such that the first power supply line 21 andthe second power supply line 29 have different polarities, and a voltagedifference occurs between the first electrode 23 and the secondelectrode 27. Due to such a voltage difference, positive ions aregenerated as a result of an electrode reaction in an anode. The positiveions generated from the above-stated reaction move to a cathode and passthrough the membrane 25 while pulling the operation fluid together suchthat a pressure (a pumping force) is generated.

That is, such an electrochemical reaction enables ions and the operationfluid to move to the space 19 a of the first pump housing 19 or thespace 31 a of the second pump housing 31 by passing through the membrane25.

When the polarity of power of the first electrode 23 and the polarity ofpower of the second electrode 27 are alternately supplied through thefirst power supply line 21 and the second power supply line 29, theoperation fluid can be iteratively moved to the space 69 a of the firstpump housing 19 and the space 31 a of the second pump housing 31 by theabove-described electrochemical reaction.

That is, when an electrode which functions as an anode is changed toserve as a cathode due to alternation of the voltage polarity, anelectro-chemical reactant consumed when the electrode is used as ananode can be recovered when the electrode is used as a cathode, and viceversa. Accordingly, the electro-osmosis pump can be continuously driven.

Then, the first diaphragm 17 and the second diaphragm 33 are deformedand a pressure is generated. Such a pressure is applied to a spacebetween the connector 1 and the first diaphragm 17.

Then, the liquid medicine is introduced into the liquid medicine inlet 1b through the liquid medicine inflow extension pipeline 7 a by thepressure. The introduced liquid medicine may be injected into a humanbody while being discharged along the liquid medicine outlet 1 c and theliquid medicine discharge extension pipeline 7 b.

In this case, the inflow check valve 9 and the discharge check valve 11allow the liquid medicine to move along only one direction. Thus, theelectro-osmosis pump according to the exemplary embodiment of thepresent invention can safely inject liquid medicine into a human bodywhile using low power.

In particular, since the operation fluid of the driver 5 and the liquidmedicine are separated from each other, the electro-osmosis pump 5 ofthe exemplary embodiment of the present invention can prevent an activecomponent included in the liquid medicine from being spoiled due to anelectro-chemical reaction.

In addition, according to the present invention, a component included inthe operation fluid of the driver 55 can be prevented from beingtransmitted to the liquid medicine such that a wider range of liquidmedicine or operation fluid is applicable.

In addition, according to the present invention, a check valve of whichan opening pressure is very low is used so that a reaction speed of thecheck valve is very fast, and accordingly, the pump can be driven withlow power and high efficiency as a whole.

While this invention has been described in connection with what ispresently considered to be practical exemplary embodiments, it is to beunderstood that the invention is not limited to the disclosedembodiments. On the contrary, it is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the appended claims.

What is claimed is:
 1. A patch-type liquid medicine delivery deviceconfigured to attach to a human body, the device comprising: a driverconfigured to move a liquid medicine toward the body by applyingpressure to the liquid medicine while being separated from the liquidmedicine; and a check valve assembly coupled to the driver, wherein theliquid medicine pushed by the driver passes through the check valveassembly, wherein the driver comprises: a first pump housing providedwith a space where an operation fluid is received; a first electrode; amembrane of which one side is combined to the first electrode; a secondelectrode combined to other side of the membrane; a second pump housingcombined to one side of the second electrode and provided with a spacewhere the operation fluid is received; and a diaphragm combined to thefirst pump housing, wherein the check valve assembly comprises: a valvehousing comprising a liquid medicine inflow extension pipeline and aliquid medicine discharge extension pipeline; an inflow check valvepassing the liquid medicine toward the driver; a discharge check valvepassing the liquid medicine in a direction of injection into a humanbody; a first fixing hole fixing the inflow check valve to the valvehousing; and a second fixing hole fixing the discharge check valve tothe valve housing, wherein the liquid medicine inflow extension pipelineof the valve housing is disposed between the driver and the inflow checkvalve, wherein the second fixing hole is disposed between the driver andthe discharge check valve, and wherein one end of the first fixing holein an axial direction is fitted to the liquid medicine inflow extensionpipeline of the valve housing and other end of the first fixing hole inthe axial direction is exposed to the outside and is not coupled to thedriver.
 2. The device of claim 1 further comprising: a connectorprovided with a liquid medicine inlet and a liquid medicine outlet,wherein the connector is disposed between the driver and the check valveassembly.
 3. The device of claim 1, wherein the driver further comprisesa diaphragm combined to the first pump housing.
 4. The device of claim3, wherein the inflow check valve passes the liquid medicine toward thediaphragm of the driver.
 5. The device of claim 3, wherein the diaphragmof the driver pushes the liquid medicine toward the check valveassembly.
 6. The device of claim 1, wherein one end of the second fixinghole in the axial direction is fitted to the liquid medicine dischargeextension pipeline of the valve housing and other end of the secondfixing hole in the axial direction is coupled to the driver.
 7. Thedevice of claim 1, wherein the driver further comprises a diaphragmcombined to the second pump housing.
 8. The device of claim 3, whereinthe space of the first pump housing and the space of the second pumphousing penetrate along the axial direction, wherein the space of thefirst pump housing is blocked by the diaphragm.
 9. The device of claim7, wherein the space of the first pump housing and the space of thesecond pump housing penetrate along the axial direction, wherein thespace of the second pump housing is blocked by the diaphragm.
 10. Thedevice of claim 2, wherein a space in which the liquid medicine isintroduced into through the liquid medicine inlet and discharged throughthe liquid medicine outlet is formed between the connector and thedriver.
 11. The device of claim 1, wherein the membrane is formed of aporous material through which an operation fluid and ions aretransferred.
 12. The device of claim 1, wherein the membrane is formedof an insulator.
 13. The device of claim 3, wherein the diaphragm isprovided with a wrinkle portion that is formed as protrusions anddepressions.
 14. The device of claim 7, wherein the diaphragm isprovided with a wrinkle portion that is formed as protrusions anddepressions.